Etiology:  In Mongolian gerbils, spontaneous cholesteatomas arise from the tympanic membrane and the medial ear canal, there is accumulation of keratin forming plugs.  Otitis media may be seen in advanced cases of aural cholesteatoma.

Incidence:  The incidence of spontaneous aural cholesteatomas is moderate, and occurs in elderly gerbils two years and older.

Clinical Signs:  Symptoms include pronounced head tilt, scratching and circling.

Diagnosis:  Diagnosis is made based on clinical signs and confirmed by histopathology.